Since she was born my youngest daughter has been a guinea pig for all sorts of developmental experiments. At five, I figured she was ready for Walter Mishel’s marshmallow test. I left her alone in the kitchen with a single fluffy pink marshmallow on a plate and told her that if she could resist eating it, she could have two marshmallows when I came back. Fifteen minutes later I returned to find the marshmallow untouched. True to my word, I handed her a second one and she said “If we do it again can I get third?”

Mishel devised the experiment in the 1960’s to measure our capacity for ‘delayed gratification’. The children in his original study were tracked for the next forty years and the results showed that the kids who managed to wait for a second marshmallow had fewer behavioural problems, achieved higher SAT scores and had better social cognitive and emotional coping in adolescence. Needless to say, I chose to interpret my daughter’s restraint as evidence of her superior cognitive abilities, but a recent study from Rochester University suggests that, in children, the ability to resist temptation is heavily influenced by the certainty of the reward.

The Rochester team replicated Mishel’s experiment, but prior to exposing the kids to the marshmallows, they were put into two groups. One group was promised art materials for a project and the promise was kept. The other group was promised art materials, but they never materialised. All the children were subsequently subject to the marshmallow test and the ones who had experienced the ‘reliable’ interaction waited on average four times longer (12 minutes versus 3 minutes) than the children who had been in the ‘unreliable’ condition.

These finding are consistent with other research which shows that children are sensitive to uncertainty when it comes to future rewards and also, that children with absent fathers prefer more immediate rewards, over larger, but delayed ones. Basically, if kids are used to having things taken away from them, or parents generally don’t live up to their promises, ‘not’ waiting’ is the rational choice. Viewed in this context, a child’s performance in Mishel’s test is not a reflection of intellectual ability, but a reflection of the consistency, or stability, of the environment that a child has been brought up in.

To extrapolate from marshmallows to marriage might seem like a stretch, but in adult relationships, our behaviour is similarly influenced by our expectation of outcome, so, for example, being the child of divorced parents increases the risk that you will divorce too. According to Professor Nicholas Wolfinger, author of ‘Understanding the Divorce Cycle: The Children of Divorce in Their Own Marriages’, if one spouse in a marriage has parents who have divorced, their risk of divorce is 50% higher and if both spouses have parents who have divorced, their risk of divorce is 200% higher. The majority of children who have experienced divorce have also experienced what it is like to live in an unhappy family situation, so its hardly surprising that 70% of them believe that divorce is an adequate solution to marital difficulties. When you learn to expect that promises will be broken, there is no virtue in waiting to be proven right.

I am the child of divorced parents, so was my first husband, and so is my second. When I add this chequered legacy to the existing ubiquity of divorce, the chance of any of my four daughters finding enduring love seem slim. However, psychologists Ming Cui and Frank Fincham have studied the ways in which parental relationships affect children’s perceptions and their research shows that how parents behave, how well they communicate and how committed they are to each other, regardless of whether they are married, or divorced, are the most significant factors influencing a child’s own relationships in adulthood. We can’t change the past, but we can influence the future by encouraging, rather than inhibiting, the next generation’s capacity for commitment. To shield our children from negative parental interactions requires discipline, restraint and trust… but it is no coincidence that those qualities are exactly the ones that are required by any child who succeeds at waiting for a second marshmallow.